Presentation #236.05 in the session The Present and Future of High Resolution Imaging with Optical and Radio Interferometry.
In recent years new radio interferometers have brought new features and improvements such as larger fields-of-view, better instantaneous coverage with high fidelity, improvements at low observing frequencies, and broader bandwidths. These improvements have opened up new possibilities in radio imaging, such as imaging on a wide variety of timescales from the usual long, multi-hour observations down to timescales of seconds. Furthermore, wide observing bandwidths allows for both increased sensitivity and for splitting up the bandwidth to commensally search for narrow-bandwidth phenomena such as fast radio bursts in the image plane. The MeerKAT radio telescope is a recent example of such an instrument that enables these kinds of studies. We have carried out commensal transient searches of MeerKAT observations as part of the ThunderKAT collaboration, searching on multiple timescales of months down to seconds, along with splitting the bandwidth in half on the shortest timescales to look for possible narrow-bandwidth transients. In the process, we have developed tools and methods to make these kinds of commensal transient searches more practical. We use these tools and new methods to find transients and variables and to place constraints on transient rates.